The invention relates to a side air bag system and, more particularly to a side air bag system having at least one inflatable air bag, a supporting strap which can be tensioned in the area of the inflated air bag sa well as operating devices for tensioning the supporting strap and inflating the air bag into its protective position. Furthermore, the invention relates to an operating process for such a side air bag system. In addition, the invention includes a motor vehicle seat equipped with such a side air bag system.
Nowadays, air bag systems are part of the standard equipment of many motor vehicles and offer their occupants a situation-related protection. For this purpose, air bag systems are used not only in front of the occupants for protecting the head which, in the event of a collision, is accelerated toward the front, but air bag systems are also provided laterally of the occupants in order to protect the occupants' head and thorax in the event of a side impact.
German Patent Document DE 44 36 139 C1 describes a passenger seat which has a side impact protection. Such a passenger seat, particularly for motor vehicles, has, at least on one of its sides, a laterally integrated side air bag which, when it is triggered, emerges from the seat contour, can be inflated and, as a result, laterally bridges the space between the seat surface and the backrest. The latter is constructed as a hose which is shortened in its longitudinal course as the result of the enlargement of the diameter connected with the inflating and, in its installed position, is fastened with its one end in the forward area of the seat surface and with its other end in the upper area of the backrest. In this case, it is not ensured that the side air bag can unfold in a perfect manner during the inflating and is not clamped in between an occupant and the vehicle body or the seat.
From German Patent Document DE 195 42 436 A1, an air bag system for a motor vehicle is known which has at least one air bag which can be filled with gas, at least one gas storage device for filling the air bag, and a holding device by means of which the air bag is held along a frame part of the vehicle body in the passenger compartment. A supporting strap is provided on the air bag which forms a lateral support for the filled air bag. The supporting strap, which is folded together with the air bag, after the triggering of the air bag, is tensioned simultaneously with its filling and extends along the outer side of the filled air bag, particularly diagonally thereto or to a vehicle window. Although the supporting strap achieves an additional guidance for the air bag when it is moved out of the covering, it cannot be excluded in this case that the air bag may catch between the supporting strap, the vehicle body parts and occupants' extremities or may be clamped between them.
The two above-described known air bag systems cannot ensure the protective effect of the air bag because the air bag may be hindered during the inflating and can therefore possibly not assume its intended shape and position, whereby the safety effect of such a side air bag, as well as of a thorax air bag or head air bag, is restricted.
It is an object of the invention to provide a side air bag system which offers a greater safety to an occupant. This object is achieved by means of a side air bag system having at least one inflatable air bag, a supporting strap which can be tensioned in the area of the inflated air bag as well as operating devices for tensioning the supporting strap and inflating the air bag into its protective position. The tensioning supporting strap is coupled with the air bag such that the tensioning supporting strap pushes the air bag out of its folded position into its protective position.
Furthermore, the invention has the object of providing an operating process for a side air bag system, by means of which the latter provides an increased protection for the occupant. For achieving this object, the invention provides an operating process for a side air bag system characterized in that the unfolding of the air bag from a folded condition into an at least essentially unfolded condition is at least supported by the tensioning of the supporting strap.
It is also an object of the invention to provide a motor vehicle seat with a side air bag system which increases an occupant's safety. According to the invention, this object is achieved by means of a motor vehicle seat having a seat element and a backrest element as well as a side air bag system which has at least one air bag which can be inflated by means of operating devices and which, in its folded condition, is arranged in an, in particular, angular accommodation space which extends on one side of the motor vehicle seat over the seat element and the backrest element. In the inflated condition, the air bag extends in a protective position between the seat element and the backrest element. In this case, a supporting strap is arranged along the air bag, which supporting strap can be tensioned in the area of the inflated air bag and is coupled with it such that the tensioning supporting strap pushes the air bag into its protective position. The supporting strap together with the folded air bag is arranged in the optionally angular accommodation space. The operating devices during the triggering of the air bag are designed for acting upon the supporting strap in order to tension it into the protective position.
A side air bag system according to the invention therefore contains at least one inflatable air bag, a supporting strap which can be tensioned in the area of the inflated air bag and operating devices for inflating the air bag and tensioning the supporting strap in its protective positions. The supporting strap is coupled with the air bag such that the tensioning supporting strap pushes the air bag out of its folded position into its protective position.
By means of the tensioning of the supporting strap, in addition to its own endeavors caused by the inflating, the air bag is reliably pushed into its protective position. As the result of the supporting strap, the air bag can reach its protective position also through the smallest spaces without being clamped in before contacting an occupant with a vehicle part between the occupant and the vehicle part.
Because of the fact that, according to the invention, the supporting strap extends along the cushion-type or hose-type air bag when it is inflated, the latter is advantageously reinforced, which has the result that it can absorb higher forces. This also has the advantage that the combination of the air bag and the supporting strap, on the one hand, provides a firm hold for occupants, which saves the occupants from impacting the vehicle body, and, on the other hand, forms an effective obstacle for objects penetrating into the interior of the vehicle.
By means of the invention, it is therefore, on the one hand, ensured that the air bag can reliably take up its protective position, in which its inflated gas bag according to its purpose absorbs kinetic energy from occupants and, on the other hand, an effective barrier is created which carries out an additional protective function in that it prevents the occupant from sliding "against" the accident. The tensioning of the supporting strap also advantageously provides the occupant with a correct momentum or thrust toward the interior of the vehicle, thus away from the accident. It is also advantageous that, by means of the supporting strap, a further reinforcement of the vehicle body is achieved against the effects of the accident, the possible deforming of the tensioned supporting strap itself having an energy-consuming effect.
Preferably, the air bag is constructed in the manner of a cushion in order to extend in its protective position between a backrest element and a seat element of a seat. The air bag may also be constructed is the form of a hose, the supporting strap then being arranged along the hose-type air bag and, in the course of its length, being coupled with it such that the tensioning supporting strap pushes the air bag into its protective position.
According to another preferred embodiment of the invention, the air bag has such an at least essentially triangular shape that, in the protective position of the air bag, a first side matches the shape along a backrest element and a second side matches the shape along a seat element of a seat, and the third side extends between the backrest element and the seat element of the seat.
In the case of a side air bag system according to the invention, the tensioned supporting strap and the inflated air bag or one side thereof extend at least approximately in parallel with respect to one another.
According to another preferred further development of the side air bag system according to the invention, the supporting strap has an end area facing the operating devices in which it is coupled with the operating devices and which can be displaced relative to the corresponding end area of the air bag which is stationary with respect to the operating devices, and an end area facing away from the operating devices in which it is stationary relative to the corresponding end area of the air bag. In other words, the supporting strap is fixed on one end and, on the other end assigned to the operating devices, is coupled with the operating devices. This has the advantage that only one end of the supporting strap has to be pulled in order to tension it, and, as a result, only a minimal expenditure is required for the operating devices. For the tensioning of the supporting strap, the operating devices can be constructed analogously to belt tightening devices and air bag systems, so that the respective previous technology, particularly from the present applicant's earlier applications, is part of the disclosure content of these documents. In particular, these are the older German Patent Applications DE 196 41 224.2, DE 197 03 945.6, DE 197 07 998.9, DE 197 09 257.8, DE 197 12 782.7, DE 197 15 463.8, DE 197 26 878.1, DE 197 33 896.8 and DE 197 38 727.6.
It is another advantageous embodiment of the side air bag system according to the invention that the supporting strap is situated in the interior of the air bag or in a guide assigned to its exterior cover. As a result, it is ensured that an occupant cannot strike against the supporting strap itself but the latter is always surrounded by the filled and therefore damping gas bag of the air bag. However, as an alternative, it may also be provided that the supporting strap is connected, at least in areas, with the outer cover of the air bag or is constructed integrally therewith. As a result, particularly when the supporting strap is arranged on the side of the air bag facing away from an occupant, the whole inflated air bag is situated in a damping manner between an occupant and the supporting strap.
When the operating devices are designed for tensioning the supporting strap at least partially before the inflating of the air bag is started, as may be provided in another embodiment of the invention, the advantage is achieved that the air bag is not yet inflated and therefore folded together relatively thinly as long as it is moved into its protective position by the tensioning supporting strap. In this condition, the air bag can be pulled without any problem even through very small spaces. If the air bag is inflated during this operation, it presses the occupant virtually back onto his seat, which can be achieved by the fact that the operating devices are designed for inflating the air bag during the tensioning of the supporting strap and in particular starting simultaneously therewith.
For this purpose, it is particularly provided according to the invention that a bracing piston is provided for operating the tensionable supporting strap in, for example, a propelling charge container with two different pressure levels. In general terms, this embodiment of the invention relates to the fact that the operating or tensioning of the tensionable supporting strap is carried out by means of a first pressure level, and the inflating of the air bag takes place by means of a second pressure level. For example, a high-pressure level of approximately 300 bar in a high-pressure chamber can be used for tensioning the supporting strap and a lower pressure level of approximately 100 bar in a low-pressure chamber can be used for inflating the air bag, which both can be triggered by means of a single electric ignition. Pressure chambers are provided corresponding to the two different pressure levels, which pressure chambers can be blocked with respect to one another by at least one valve and preferably different valves. In this case, the operation according to the invention is, for example, as follows: During the bracing of, for example, a thorax bag, for the effective movement of the piston, for example, approximately 300 bar are required, for example, from a pyrotechnical propelling charge container. In contrast, for the inflating of the bag, no more than, for example, 100 bar may be used so that no more than 1 bar will occur in the bag.
Within the scope of the invention, the above-explained embodiment can be achieved, for example, by a conventional particularly electric propelling charge container whose ignition ignites advantageously through corresponding holes from the high-pressure chamber through to the low-pressure chamber and there ignites a, for example, pyrotechnical gas generator. In the case of such an embodiment, such ignition holes must then be closed immediately so that the filling gas for the air bag generated by means of the gas generator is supplied only to the air bag and is not lost for its filling in that it escapes into the cylinder for guiding the piston for tensioning the supporting or tensioning rope.
The operating devices of a side air bag system according to the invention preferably contain a tensioning device for the supporting strap and a filling device for the air bag, thus two separate energy accumulators, the tensioning device and the filling device preferably being coupled and particularly preferably mutually interacting. Within the scope of the invention, this is preferably further developed in that the filling device contains a gas generator and/or a gas storage device. As an alternative or in addition, the tensioning device may contain an energy accumulator and driving devices which can be acted upon by it, for the tensioning of the supporting strap, and the driving devices may particularly contain a preferably releasable return stop and particularly preferably a return stop which, with respect to the triggering of the operating devices, automatically releases in a time-delayed manner. The latter prevents that a tension of the supporting strap which has once been achieved loosens because of a high counterforce, and then that the air bag with the supporting strap locks an occupant in a vehicle involved in an accident.
By means of one of the preferred combinations according to which the gas generator and/or the gas storage device of the filling device is at least one portion of the energy accumulator of the tensioning device, or the energy accumulator of the tensioning device is at least one portion of the gas generator and/or of the gas storage device of the filling device, a particularly economical and simple construction of the operating devices is achieved.
It may also preferably be provided that the air bag is connected in a gas-tight manner with the gas generator and/or the gas storage device, and the supporting strap is permanently coupled to the driving devices or, in particular, can be automatically coupled by their triggering. Particularly the latter permits, in the case of a seat which can be adjusted, for example, in its height, inclination, and/or in the longitudinal direction of the vehicle, the mounting of the operating devices outside the adjustable seat parts, for example, below the seat. In a further development of the invention of the latter, the driving devices may contain a piston which can be acted upon by the energy accumulator, to which piston the supporting strap is coupled or, in particular, can be automatically coupled by the triggering of the driving devices.
Further embodiments of a side air bag system according to the invention may comprise that a pyrotechnical activation and particularly an ignition of the gas generator/gas storage device of the filling device and/or of the energy accumulator of the tensioning devices is provided, and/or at least one of these components is designed in a multi-stage manner.
It is also preferred that the gas generator and/or the gas storage device of the filling device and/or the energy accumulator of the tensioning device or optionally at least a first stage of the gas generator and/or of the gas storage device of the filling device and/or of the energy accumulator of the tensioning device or optionally their pyrotechnical activation or ignition in the case of a side air bag system according to the invention, can be electrically triggered and, in particular, ignited. This can be further developed in that at least a second stage of the gas generator and/or of the gas storage device of the filling device and/or of the energy accumulator of the tensioning device or optionally their pyrotechnical activation or ignition can be mechanically triggered and, in particular, ignited.
For increasing the reliability at least of the mechanical parts of the electric and/or mechanical triggering and particularly of the ignition, these modules may be provided twice and can be acted upon simultaneously but independently of one another.
When, on its end assigned to the operating devices, the supporting strap is formed by a material which is resistant to the operating temperatures in the operating devices, advantageously particularly effective operating devices can be used, in which, however, temperatures occur which the remaining supporting strap would not withstand.
Preferably, the supporting strap has, at least in the area of the inflated air bag, that is, when it is in its protective position, a width which is significantly larger than its thickness, and the width of the supporting strap is, in particular, in the range of approximately 10% to approximately 90%, preferably of approximately 20% to approximately 60%, and particularly preferably of approximately 25% to approximately 40% of the diameter of the air bag.
If, as according to another preferred further development of the invention, in the case of a side air bag arrangement, two air bags are coupled with pertaining supporting straps for a use on both sides of an occupant, and particularly can be operated by way of common operating devices, in the event of an accident, an occupant is protected on both sides and, in addition, is securely held on his seat. The common operating devices of both air bags with pertaining supporting straps permit a low-cost as well as space-saving and weight-saving design.
Although reference was made above at points to the combination of the side air bag system according to the invention with a motor vehicle, this is not absolutely necessary. Within the scope of the invention, the air bag together with the supporting strap of the side air bag system may also be appropriately accommodated in body parts of the vehicle, for example, in the area of the A-column and the adjoining roof strut pointing toward the rear with respect to the normal driving direction; the B-column and the possibly adjoining roof strut pointing toward the rear; the B-column and preceding roof struts pointing toward the front, possibly the C-column and preceding roof struts pointing toward the front, the dashboard holding device and lateral vehicle body parts, etc., and may be inflated and tensioned. If in this case, as in the case of the accommodation in a motor vehicle seat which will be discussed in greater detail in the following, the air bag and the supporting strap, before their triggering, are arranged in an angular accommodation space and are designed such that, in their protective position, they span the angle formed by the angular accommodation space, a protective position of the air bag and the supporting strap can be optimally defined ahead of time according to the vehicle model, shape and size.
The operating process also created by the present invention relates to a side air bag system with at least one inflatable air bag, a supporting strap which can be tensioned in the area of the inflated air bag and operating devices for inflating the air bag and tensioning the supporting strap into their final protective positions. According to the process, it is provided in this case, while achieving the objects indicated above and with the advantages indicated with respect to the system variants, that the unfolding of the air bag from a folded condition into an at least essentially unfolded condition is at least supported by the tensioning of the supporting strap. The unfolding may at least partially be a stretching operation.
Analogously to the system variants, it can further be implemented as provided in the case of the operating process according to the invention that the stretching of the supporting strap is first started before the inflating of the air bag begins. As an alternative, which also has advantages, the stretching of the supporting strap and the inflating of the air bag can also be started at least essentially simultaneously after the triggering of the side air bag system.
Preferably a further development of the operating process according to the invention provides that, by means of the triggering of the side air bag system, a filling gas for the air bag is generated or released and driving devices are acted upon to which the supporting strap is connected.
Within the scope of the invention, a motor vehicle seat is also provided which contains a seat element and a backrest element as well as a side air bag system which has at least one particularly cushion-type or hose-type air bag which can be inflated by means of operating devices and which, in its folded condition, is arranged in an angular accommodation space which extends on one side of the motor vehicle seat over the seat element and the backrest element and which, in the inflated condition, extends in a protective position partially diagonally between the seat element and the backrest element. In this case, it is provided that a supporting strap is arranged along the air bag, which supporting strap can be tensioned in the area of the inflated air bag and, in the course of its length, is coupled with it such that the tensioning supporting strap pushes the air bag into its protective position, that the supporting strap together with the folded air bag is arranged in the angular accommodation space, and that the operating devices during the triggering of the air bag are designed for acting upon the supporting strap in order to tension it into the protective position.
In the case of a motor vehicle seat according to the invention, before their triggering, the air bag and the supporting strap can be situated behind a panelling or tear seams in the accommodation space.
A preferred further development of the motor vehicle according to the invention consists of the fact that the operating devices are arranged below the seat element in the driving direction or particularly transversely thereto, and, in particular, are reinforcingly connected with the seat structure and/or the vehicle structure. Particularly the arrangement of the operating devices below the seat element transversely to the driving direction is a preferred variant which can also be awarded a separate inventive significance, optionally in the case of a seat or a frame structure of the motor vehicle with operating devices of a side air bag system or a use of a transverse spar of a frame structure of the motor vehicle for receiving the operating devices of a side air bag system. Specifically in the area of the seat, this construction achieves a reinforcement with respect to a side impact, which by the use of this technology in addition to the conventional existing structure increases the safety or can be used for structural savings in the case of the normally existing structure while maintaining the safety standard.
The advantages of another embodiment of the motor vehicle seat according to the invention were explained above, in which one air bag respectively with its assigned supporting strap is provided on both sides of the seat, and in which preferably both air bag and supporting straps can be acted upon by common operating devices.
Height, inclination and/or longitudinal adjusting possibilities in the case of a seat can be combined with operating devices arranged outside the adjustable seat components without any reduction of comfort and functions, if the supporting strap and/or the air bag is coupled by way of compensating devices to the operating devices or can be coupled when the side air bag system is triggered, which was also discussed in conjunction with the side air bag system according to the invention.
A person skilled in the art can easily find additional objects, characteristics and advantages in the present documents, including combinations with characteristics from the applicant's above-indicated earlier patent applications. In particular, advantageous and preferred further developments of the invention and their above-described embodiments are found in the respective dependent claims and their combinations.
In the following, the invention will be described with reference to the drawing by means of concrete embodiments.